A new method of computing the conductivity tensor of brain tissue based on water diffusion tensor

The conductivity of brain tissue is an important parameter in EEG/MEG research. A new method was proposed for getting these parameters from the view of electrochemistry based on diffusion tensor imaging (DTI) using Stokes-Einstein and Nernst-Einstein equations. The method was tested on DTI data of a human subject, and the result was compared to the experiential conductivity of different brain tissues (white matter, grey matter, CSF). It was showed that the more anisotropic the tissue was, the further the conductivity tensor eigenvalue of it deviated, illuminating the necessary of including anisotropic conductivity in EEG/MEG. This method was based on DTI data incorporating the factor of the concentration of the ions in brain liquid, and provided an effective approach of calculating anisotropic conductivity of brain tissue.